KR20000010946A - Process for the preparation of an ethylene and alpha-olefin copolymer - Google Patents

Abstract

PURPOSE: A process preparing an ethylene and alpha-olefin copolymer is conducted in the presence of a novel transition metal complex and cocatalyst. CONSTITUTION: The process is further characterizable in that the transition metal complex is a reduced transition metal complex, selectable from groups 4-6 of the Periodic System of the Elements, with a multidentate monoanionic ligand and with two monoanionic ligands, at a temperature of between 100 and 220°C. In particular, the reduced transition metal in the complex is titanium (Ti (III)).

Description

Process for preparing ethylene and α-olefin copolymer

1. Field of Invention

The present invention relates to a method for producing an ethylene-α-olefin copolymer in which the ethylene content is about 20 to 90% by weight in the temperature range of 100-220 ° C., and the catalyst composition is composed of a transition metal complex and a cocatalyst.

2. Technology in related fields

A process for preparing an ethylene / α-olefin copolymer is known from US Pat. No. 5,491,207, wherein the cyclopentadiene-based (combined with cocatalyst) transition metal complex is an ethylene having an ethylene content in the range of about 20-90 mol% Used to prepare the / α-olefin copolymer. Hereinafter, the term "copolymer" means a polymer formed from two kinds of monomer constructs, ie ethylene and one or more α-olefins.

The method of US Pat. No. 5,491,207 proceeds at a relatively low temperature (-10 ° C. to about 100 ° C.), making it less attractive economically. The method needs to proceed at high temperature. There is also a need for a high temperature polymerization method that does not require too high pressure, but otherwise, the cost of the high pressure method could eliminate the advantages of the high temperature method.

Summary of the Invention

It is therefore an object of the present invention to address the above mentioned needs as well as to solve the above problems associated with the related art. According to the principles of the present invention, the above object is an ethylene / α-olefin copolymer in which the content of ethylene is about 20 to 90% by weight in the temperature range of 100-220 ° C., and the catalyst composition consists of a transition metal complex and a cocatalyst Obtained by presenting a method for producing

Another object of the present invention is to provide an ethylene / α-olefin copolymer obtained by a polymerization method using the catalyst composition of the present invention.

In this process, the polymerization of ethylene and at least one [addition] α-olefin is carried out under effective copolymerization conditions at a temperature of 100 ° C. to 220 ° C. under the influence of the catalyst composition.

The catalyst composition consists of a reduced valence transition metal (M), a polydentate monoanionic ligand (X), two monoanionic ligands (L), and optionally an additional ligand (K) selected from Groups 4-6 of the Periodic Table of the Elements. At least one complex. In particular, the complex of the catalyst composition of the present invention is represented by the following general formula (1):

(In Formula 1,

M is a reduced transition metal selected from group 4, 5 or 6 of the Periodic Table of the Elements;

X is a multidentate monoanionic ligand represented by the general formula (Ar-R _t- ) _s Y (-R _t -DR ' _n ) _q ; From here

Y is a cyclopentadienyl, amido (-NR'-) or phosphido group, bonded to a reduced transition metal (M);

R is at least one element selected from the group consisting of (iv) a linking group between the Y and DR'n groups and (ii) a linking group between the Y and Ar groups, wherein the ligand (X) comprises one or more R groups Groups are the same or different from one another;

D is an electron-donor heteroatom selected from group 15 or 16 of the Periodic Table of the Elements;

R ′ is a substituent selected from the group consisting of hydrogen, a hydrocarbon radical and a heteroatom-containing component, except that it cannot be hydrogen when directly bonded to an electron-donor heteroatom (D), wherein the polydentate monoanionic ligand When (X) contains one or more substituents (R '), the substituents (R') are the same or different from one another;

Ar is an electron-donor aryl group;

L is a monoanionic ligand that is bound to the reduced transition metal (M), where the monoanionic ligand (L) is a ligand consisting of a cyclopentadienyl, amido (-NR'-) or phosphido (-PR'-) group Monoanionic ligands (L) may be the same as or different from each other;

K is a neutral or anionic ligand that is bound to the reduced transition metal (M), wherein the transition metal complex contains one or more ligands (K), and the ligands (K) may be the same or different from each other;

m is the number of K ligands, m is 0 for M ³⁺ , 1 for M ⁴⁺ , 2 for M ⁵⁺ when K ligand is an anionic ligand, and m is each for K One by one for the neutral K ligand;

n is the number of R 'groups bonded to the electron-donor heteroatom (D), where n is 2 when D is selected from Group 15 of the Periodic Table of the Elements, n is 1 when D is selected from Group 16 of the Periodic Table of the Elements ;

q and s are the number of (-R _t -DR ' _n ) groups and (Ar-R _t- ) groups respectively bonded to the Y group, and q + s is an integer of 1 or more; And

t is (ⅰ) and Y and the number of R groups connecting each Ar group (ⅱ) the Y and DR _'n groups, wherein t is independently selected as 0 or 1)

The transition metal complex of formula (1) makes it possible to produce ethylene / α-olefin copolymers at temperatures of 100 ° C. to 220 ° C., while other known catalysts for this kind of polymerization are copolymers at temperatures above 100 ° C. Do not form (they are only active at temperatures below 100 ° C .; U.S. Pat. No. 5,491,207 shows a temperature of −10 ° C. to 100 ° C., which represents an embodiment conducted at a temperature of 35 ° C. to 50 ° C. I knew that.

The method of the present invention is suitable for preparing copolymers having M _n (number average molecular weight (measured by SEC-DV (size fractional analysis / differential viscometer combination)) as low as about 100). The temperature at which the polymerization takes place is one of the parameters controlling the M _n value. In essence, ethylene / a-olefin copolymers having M _n between about 100 and about 500,000 can be prepared.

Copolymers having a molecular weight (M _n ) between about 100 and about 30,000 are preferably prepared by the polymerization process at a temperature between about 135 ° C. and about 220 ° C .; Copolymers having a molecular weight (M _n ) between about 20,000 and about 100,000 are preferably prepared by the polymerization process at a temperature of about 115 ° C to about 180 ° C.

The copolymer also has an ethylene content of about 20 to about 90 weight percent. The copolymer may be amorphous, a product having an ethylene content of about 30 to about 70 weight percent, or may be a semicrystal, which is a product having an ethylene content of about 70 to about 90 weight percent.

The pressure at which the polymerization proceeds is preferably about 100 MPa or less. Pressures below 10 MPa are sufficient for good catalytic activity in many cases. CA-A-2,11,057 describes a process for preparing ethylene / butene low molecular weight copolymers at comparatively high pressures of 1,330 bar corresponding to very low catalytic activity at normal pressure (Comparative Example 2).

Other methods known in the art for preparing low molecular weight ethylene copolymers start with low molecular weight products (eg by shearing) or extreme amounts of chains to maintain low molecular weight during polymerization. Start with a regulator (eg hydrogen or diethylzinc). In all cases, the temperature at which the copolymer is prepared is as low as -10 to 100 ° C.

These and other objects, features and advantages of the present invention will become apparent from the following detailed description and claims.

The accompanying drawings illustrate the invention. In the drawing:

1 is a schematic diagram of a cationic active site of a trivalent catalyst complex according to an embodiment of the present invention; And

Figure 2 is a schematic diagram of the neutral active site of the trivalent catalyst complex of the cationic ligand of the conventional catalyst complex according to WO-A-93 / 19104.

Various components (groups) of the transition metal complexes are described in more detail below.

(a) transition metal (M)

The transition metal in the complex is selected from Groups 4-6 of the Periodic Table of the Elements. As mentioned herein, all references to the Periodic Table of Elements refer to the interpretations described in the new IUPAC annotation appearing in the cover of the Handbook of Chemistry and Physics, 70th Edition, 1989/1990, whose full description Later incorporated by reference. The transition metal is preferably selected from Group 4 of the Periodic Table of the Elements, most preferably titanium (Ti).

The transition metal is present in reduced form in the complex, which means that the transition metal is in a reduced oxidation state. As mentioned above, "reduced oxidation state" means an oxidation state that is at least zero but lower than the highest possible oxidation state of the metal (eg, the reduced oxidation state is at most M for Group 4 transition metals). ³⁺ , M ⁴⁺ for group 5 transition metals, and M ⁵⁺ for group 6 transition metals).

(b) X ligand

X ligand is a multidentate monoanionic ligand represented by the general formula (Ar-R _t- ) _s Y (-R _t -DR ' _n ) _q .

As mentioned herein, polydentate monoanionic ligands are covalently bound to the transition metal (M) reduced at one site (anion site, Y), and (iii) coordination to the transition metal at the other site (two sites). Or (ii) a plurality of coordination bonds at different sites (three, four, etc.). The coordination bond may occur via, for example, a D heteroatom or an Ar group. Examples of tridentate monoanion ligands include, but are not limited to, YR _t -DR ' _n-1 -R _t -DR' _n and Y (-R-DR ' _n ) ₂ . However, heteroatoms or aryl substituents do not coordinate Y to the reduced transition metal (M) as long as at least one coordination bond is formed between the electron-donor group (D) or the electron donor Ar group and the reduced transition metal (M). It can be present in the weather.

R represents a linking group or a bridge group between DR ′ _n and Y, an electron donor aryl (Ar) group, and Y. Since R is optional, "t" may be zero. R group is described in more detail below (d).

(c) group Y

The Y group of the polydentate monoanionic ligand (X) is preferably a cyclopentadienyl, amido (-NR'-) or phosphido (-PR'-) group.

Most preferably, the Y group is a cyclopentadienyl ligand (Cp group). As mentioned herein, the term cyclopentadienyl group refers to R _t -DR ' _n wherein at least one of the substituents of the Cp group substitutes for one of the hydrogens bonded to the pentagonal ring of the Cp group via an out-of-ring substitution reaction. And other polycyclic aromatic groups containing at least one pentadiedienyl ring and substituted cyclopentadienyl groups such as indenyl, fluorenyl and benzoindenyl groups as long as they are a group or a R _t -Ar group.

Examples of polydentate monoanionic ligands having a Cp group as the Y group (or ligand) include the following (with (-R _t -DR ' _n ) or (Ar-R _t- ) substituents on the ring):

The Y group may also be a hetero cyclopentadienyl group. As mentioned herein, a heterocyclopentadienyl group means a hetero ligand derived from a cyclopentadienyl group, but at least one of the atoms defining the pentacyclic ring structure of cyclopentadienyl is heterocyclic through an in-ring substitution reaction. Replaced by an atom. Hetero Cp groups also include at least one R _t -DR ' _n or R _t -Ar group that substitutes for one of the hydrogens attached to the pentagonal ring of the Cp group via an out-of-ring substitution reaction. In the Cp group, as mentioned herein, the hetero Cp group is R _t -DR ' _n wherein at least one of the substituents of the hetero Cp group substitutes for one of hydrogen bonded to the pentagonal ring of the hetero Cp group through an out-of-ring substitution reaction. Indenyl, fluorenyl and benzoindenyl groups, and other multicyclic aromatic groups containing at least one pentadiedienyl ring, as long as it is a group or a R _t -Ar group.

Heteroatoms may be selected from Groups 14, 15 or 16 of the Periodic Table of Elements. If there is more than one heteroatom in each ring pair, the heteroatoms may be the same or different from one another. More preferably, the heteroatom is selected from group 15, and more preferably the heteroatom is phosphorus.

By way of example and without limitation, representative hetero ligands of the X groups which may be carried out in accordance with the invention are heterocyclopentadienyl groups having the structure of formula (3) wherein heterocyclopentadienyl is selected from It contains one phosphorus atom (ie a heteroatom) to be substituted:

In general, the transition metal group (M) is bonded to the Cp group via a η ⁵ bond.

The other R ′ out-of-substituted substituents on the ring of the hetero Cp group (as shown in Formula 3) can be the same as those present on the Cp group, as shown in Formula (2). As in Formula 2, at least one off-ring substituent on the pentagonal ring of the heterocyclopentadienyl group of Formula 3 is an R _t -DR ' _n or R _t -Ar group.

Numbering of Substituents for Indenyl Groups In general, the description is based on the IUPAC Nomenclature of Organic Chemistry 1979, rule A 21.1. Numbering of substitution sites for indenes is shown below. This numbering is similar to that for indenyl:

The Y group can also be an amido (-NR'-) group or a phosphido (-PR'-) group. In the above optional embodiment, the Y group contains nitrogen (N) or phosphorus (P) and (optionally) of (R _t -DR ' _n ) or (Ar-R _t- ) substituents as well as transition metals (M). Covalently bonded to the R group.

(d) R group

The R group is optional and may not be present in the X phase. Where there is no R group, the DR ' _n or Ar group is directly bonded to the Y group (ie, the DR' _n or Ar group is directly bonded to the Cp, amido or phosphido group). The presence or absence of an R group between each of the DR ′ _n and / or Ar groups is independent of each other.

Where there is at least one R group, each R group constitutes a linker between the Y groups, while between the DR ′ _n or Ar groups. The presence and size of the R group determines the accessibility of the transition metal (M) to the DR ′ _n or Ar group, which provides the desired intramolecular configuration. If the R group (or bridge) is too short or absent, the donor may not coordinate well due to ring tension. The R groups are each selected separately and can be, for example, hydrocarbon groups having 1-20 carbon atoms (eg alkylidene, arylidene, aryl alkylidene, etc.). Specific examples of the R group include, but are not limited to, methylene, ethylene, propylene, butylene, phenylene with or without substituted side chains. Preferably, the R group has the structure of formula

(-CR ' _2- ) _p

(In Formula 4, p = 1-4)

Each R ′ group of Formula 4 may be selected individually, and may be the same as the R ′ group defined at the lower end of paragraph (g).

In addition to carbon, the main chain of the R group may also contain silicon or germanium. Examples of such R groups are: dialkyl silylenes (-SiR ' _2- ), dialkyl germanylenes (-GeR' _2- ), tetra-alkyl silylenes (-SiR ' ₂ -SiR' _2- ), or tetra Alkyl silica (-SiR ' ₂ -CR' _2- ). The alkyl group in the group preferably has 1-4 carbon atoms, more preferably a methyl group or an ethyl group.

(e) DR ' _n groups

The donor group is composed of an electron-donor heteroatom (D) selected from Group 15 or 16 of the Periodic Table of the Elements and one or more substituents (R ′) bonded to D. The number (n) of R 'is determined by the nature of the heteroatom (D), where n is 2 if D is selected from group 15 and n is 1 if D is selected from group 16. The R ′ substituents attached to D may each be selected individually and may be the same as the R ′ groups defined in g) below, except that the R ′ substituents attached to D may not be hydrogen.

The hetero atom (D) is preferably selected from the group consisting of nitrogen (N), oxygen (O), phosphorus (P) and sulfur (S); More preferably, the hetero atom is nitrogen (N). Preferably, the R 'group is alkyl, more preferably an n-alkyl group having 1-20 carbon atoms, most preferably an n-alkyl group having 1-8 carbon atoms. Also may be connected to each other to form a ring structure group DR _'n in-flight two R' (e.g. DR _'n group can pyrrolidinyl date). The DR ′ _n group may form a coordination bond with the transition metal (M).

(f) Ar group

Selected electron-donor groups (or donors) are also multi-rings such as phenyl, tolyl, xylyl, mesityl, cumenyl, tetramethyl phenyl, pentamethyl phenyl (C ₆ R ' ₅ ), triphenylmethane and the like. It may be a flag. However, the electron-donor group (D) of formula 1 cannot be a substituted Cp such as an indenyl, benzoindenyl or fluorenyl group.

The complementarity of the Ar group with respect to the transition metal (M) may vary from η ¹ to η ⁶ .

(g) R 'groups

R 'groups are each a hydrocarbon radical or hydrogen having 1-20 carbon atoms (eg alkyl, aryl, aryl alkyl, etc., as shown in Table 1).

Examples of alkyl groups are methyl, ethyl, propyl, butyl, hexyl and decyl. Examples of aryl groups are phenyl, mesityl, tolyl and cumenyl. Examples of aryl alkyl groups are benzyl, pentamethylbenzyl, xylyl, styryl and trityl. Examples of other R 'groups are halides such as chloride, bromide, fluoride and iodide, methoxy, ethoxy and phenoxy.

In addition, two adjacent hydrocarbon radicals of the Y group may be connected to each other to form a ring system; Thus the Y group may be an indenyl, fluorenyl or benzoindenyl group. Indenyl, fluorenyl and / or benzoindenyl may contain one or more R ′ groups as substituents. R 'may also be a substituent which may consist of one or more heteroatoms of Groups 14-16 of the Periodic Table of the Elements in addition to or in addition to carbon and / or hydrogen. The substituent may thus be a Si-containing group, for example Si (CH ₃ ) ₃ .

(h) L

The transition metal complex contains two monoanionic ligands (L) that are bound to the transition metal (M). Examples of L group ligands that may be the same or different include a hydrogen atom; Halogen atom; Alkyl, aryl or aryl alkyl groups; Alkoxy or aryloxy groups; (Iii) sulfur groups such as sulfites, sulfates, thiols, sulfonates and thioalkyls, and (ii) groups consisting of heteroatoms selected from Groups 15 or 16 of the Periodic Table of the Elements including phosphorus compounds such as phosphites and phosphates, It is not limited to this. Two L groups may also be linked to each other to form a dianionic bidentate ring system.

These and other ligands can be tested for their suitability by simple experimentation by one of ordinary skill in the art.

L is preferably a halide and / or an alkyl or aryl group; More preferably, L is a Cl group and / or a C ₁ -C ₄ alkyl or benzyl group. However, the L group cannot be a Cp, amido or phosphido group. That is, L cannot be one of the Y groups.

(i) K ligand

K ligands are neutral or anionic groups that bind to the transition metal (M). The K group is a neutral or anionic ligand that binds to M. K may be absent when K is a neutral ligand, but when K is a monoanion, includes for K _m :

M = 0 for M ³⁺

M = 1 for M ⁴⁺

M = 2 for M ⁵⁺

On the other hand, neutral K ligands that are not anions do not belong to the same way. Thus, for each neutral K ligand, the m value (ie, the total number of K ligands) is higher than the value described above for the complex with all monoanion K ligands.

The K ligand can be a ligand as described above for the L group or a Cp group (-C ₅ R ' ₅ ), an amido group (-NR' ₂ ) or a phosphido group (-PR ' ₂ ). The K group may also be a neutral ligand such as ether, amine, phosphine, thioether, among others.

If two K groups are present, the two K groups may be linked together via an R group to form a bidentate ring system.

As can also be seen in Formula 1, the X group of the complex compound optionally contains a Y group which is linked to one or more donor groups (Ar group and / or DR ′ _n group) via the R group. The number of donor groups connected to the Y group is at least one, and at most, the number of substitution sites present on the Y group.

For example, referring to the structure according to Formula 2, at least one substitution site on the Cp group is made by the R _t -Ar group or the R _t -DR ' _n group (in this case q + s = 1). In the formula (2), when all R 'groups are R _t -Ar groups, R _t -DR' _n groups, or a combination thereof, the value (q + s) is 5.

One preferred embodiment of the catalyst composition according to the present invention consists of a transition metal complex in which a bidentate / monoanionic ligand is present and the reduced transition metal is selected from Group 4 of the Periodic Table of the Elements and has an oxidation state of +3.

In this case, the catalyst composition of the present invention is composed of a transition metal complex according to formula (5):

(In Chemical Formula 5, each part has the same meaning as defined in Chemical Formula 1, and M (III) is a transition metal selected from Group 4 of the Periodic Table of the Elements.

The transition metal complex does not have an anion K ligand (m = 0 for M ³⁺ for anion K).

WO-A-93 / 19104 describes transition metal complexes in which Group 4 transition metals are present in the reduced oxidation state (3+). The complex compound described in WO-A-93 / 19104 has the structure of Formula 6:

Cp _a (ZY) _b ML _c

The Y group in Chemical Formula 6 is a hetero atom such as nitrogen, sulfur, oxygen, or phosphorus covalently bonded to the transition metal (M) (see p. 2 of WO-A-93 / 19104). This means that the Cp _a (ZY) _b group has a monoanionic nature, and has an anionic charge previously remaining on the Cp and Y groups. Thus, the Cp _a (ZY) _b group of formula 6 contains two covalent bonds: the first is between the pentagonal ring of the Cp group and the transition metal (M), and the second is between the Y group and the transition metal (M) Is in. In contrast, the X group in the complex according to the present invention has a monoanionic property such that a covalent bond is present between the Y group (eg, Cp group) and the transition metal, and the coordination bond is one or more of the transition metal (M). It may exist between the above (Ar-R _t- ) and (-R _t -DR ' _n ) group. This changes the nature of the transition metal complex and consequently the nature of the catalyst active in the polymerization. As mentioned herein, a coordination bond, when broken, is either (i) total chargeless and unpaired electrons (eg N ₃ H: and BH ₃ ) or (ii) total charge and unpaired. It is a bond (e.g. N ₃ H-BH ₃₎ for generating ^a-e that are two kinds which (e.g. N ₃ · H ⁺ and BH _{3 ·).} On the other hand, as mentioned herein, when a covalent bond is broken, there are (ii) no total charge and unpaired electrons (eg CH ₃ and CH ₃ ) or (ii) total charge two types that do not fulfill the electronic (e.g. CH ₃ ⁺ and CH _3: ^-) is a combination (for example CH ₃ -CH ₃₎ for generating a. A discussion of coordination and covalent bonds is presented in Haaaland et al. (Angew. Chem Int. Ed. Eng. Vol. 28, 1989, p. 992), the full details of which will be incorporated by reference later.

The following description is given while pointing out that the invention is not limited to the above theory.

2, the transition metal complex described in WO-A-93 / 19104 becomes ionic after reaction with the cocatalyst. However, transition metal complexes of WO-A-93 / 19104 that are active in polymerization are transition metal complexes composed of total neutral charge (M (III) transition metals, one monoanionic ligand and one growing monoanionic polymer chain (POL). Under the assumption of polymerization). In contrast, as shown in FIG. 1, the polymerization active transition metal complex of the catalyst composition according to the present invention has cationic properties (M (III) transition metal, one monoanionic bidentate ligand, and one growing monoanionic polymer chain) Under the assumption of polymerizing a transition metal complex based on the structure of formula 5 consisting of POL).

Although the transition metal is in a reduced oxidation state, transition metal complexes having the structure of formula (7) are usually inert to the copolymerization reaction.

Cp-M (III) -L ₂

In the transition metal complex of the present invention, the presence of the DR ' _n or Ar group (donor) optionally bonded to the Y group by the R group provides a stable transition metal complex suitable for polymerization.

The donor in the molecule is preferably in the outer (internal molecule) donor because it shows a stronger and more stable coordination with respect to the transition metal complex compound.

It will also be appreciated that if its components are added directly to the polymerization reactor system and a solvent or diluent comprising a liquid monomer is used in the polymerization reactor, the catalyst system is formed in place.

The catalyst composition of the present invention also contains a cocatalyst. For example, the cocatalyst may be an organometallic compound. The metal of the organometallic compound may be selected from group 1, 2, 12 or 13 of the periodic table. Suitable metals include, for example and without limitation, sodium, lithium, zinc, magnesium and aluminum, with aluminum being preferred. At least one hydrocarbon radical is bonded directly to the metal to provide a carbon-metal bond. The hydrocarbon group used in the compound contains 1-30, preferably 1-10 carbon atoms. Examples of suitable compounds include, but are not limited to, sodium sodium, butyl lithium, diethyl zinc, butyl magnesium chloride and dibutyl magnesium. Trialkyl aluminum compounds such as, but not limited to, triethyl aluminum and tri-isobutyl aluminum; Alkyl aluminum hydrides such as di-isobutyl aluminum hydride; Alkylalkoxy organoaluminum compounds; And organoaluminum compounds comprising halogen-containing organoaluminum compounds such as diethyl aluminum chloride, diisobutyl aluminum chloride and ethylaluminum sesquichloride. The linear or cyclic aluminoxane is preferably selected as the organoaluminum compound.

In addition to, or alternatively to, the organometallic compound as a cocatalyst, the catalyst composition of the present invention may include a compound containing or generating an anion that does not or rarely coordinate when reacting with the transition metal complex of the present invention. Such compounds are described, for example, in EP-A-426,637, which will be incorporated herein by reference in its entirety. The anion is sufficiently unstable in bonding to the unsaturated monomer during copolymerization. The compounds are also mentioned in EP-A-277,003 and EP-A-277,004, the complete description of which is hereafter incorporated by reference. The compound preferably contains triaryl borane or tetraaryl borate or its aluminum equivalent. Examples of suitable cocatalysts include, but are not limited to, dimethyl anilinium tetrakis (pentafluorophenyl) borate [C ₆ H ₅ N (CH ₃ ) ₂ H] ⁺ [B (C ₆ F ₅ ) ₄ ] ^- ; Dimethyl anilinium bis (7,8-dicaboundeborate) -cobaltate (III); Tri (n-butyl) ammonium tetraphenyl borate; Triphenylcarbenium tetrakis (pentafluorophenyl) borate; Dimethylanilinium tetraphenyl borate; Tris (pentafluorophenyl) borane; And tetrakis (pentafluorophenyl) borate.

If the above non-coordinating or rarely coordinating anion is used, the transition metal complex is preferably alkylated (ie, the L group is an alkyl group). Reaction products of halogenated transition metal complexes and organometallic compounds such as triethyl aluminum (TEA) can also be used, as described in EP-A-500,944, the complete description of which is hereby incorporated by reference.

The molar ratio of cocatalyst to transition metal complex is usually in the range of about 1: 1 to about 10,000: 1, preferably about 1: 1 to 2,500: 1 when the organometallic compound is selected as the cocatalyst. If a compound containing or generating an anion that produces little or no coordination is selected as the cocatalyst, the molar ratio is usually in the range of about 1: 100 to about 1,000: 1, preferably about 1: 2 to about 250: 1. .

As will be appreciated by those skilled in the art, co-catalysts as well as transition metal complexes may be present in the catalyst composition as a single component or as a mixture of several components. For example, mixtures that need to affect the molecular properties of the polymer, such as molecular weight, especially molecular weight distribution, are preferred.

The process of the present invention is suitable for preparing semi-crystals or for preparing ethylene and α-olefin based amorphous copolymers.

Besides ethylene, the copolymers of the invention consist of one or more α-olefins. Generally the α-olefins contain 3-25 carbon atoms (although higher α-olefins are also acceptable); More preferably the α-olefin contains 3-10 carbon atoms. The α-olefin is preferably selected from the group consisting of propylene, butene, isobutene, pentene, 4-methyl pentene, hexene, octene and (α-methyl) styrene. More preferably, the α-olefin is propylene, 1-butene, 1-hexene or 1-octene. Most preferably, the α-olefin is propylene.

As already described, the process of the invention makes it possible to produce ethylene / a-olefin copolymers having a wide range of molecular weights (M _n ). Selectivity for high molecular weight products is the characterization of the copolymer by Mooney viscosity (ML _{1 + 4} , 125 ° C. by ASTM D1646). The process of the invention makes it possible to prepare ethylene / α-olefin copolymers having from 10 to 150 ML _{1 + 4} , 125 ° C.

In the process of the present invention, the catalyst composition may be used supported or unsupported. The transition metal complex or cocatalyst may be supported on a carrier. In addition, both the transition metal complex and the cocatalyst may be supported on the carrier. The carrier material for the transition metal complex and the cocatalyst may be the same material or different materials. It can also support transition metal complexes and cocatalysts on the same carrier. The supported catalyst system of the present invention which can be used for the polymerization reaction as described above may be prepared as a separate compound, or the supported catalyst system may be formed by the original method before the polymerization reaction starts. Supported catalysts are mainly used in gas phase and slurry processes. Carriers used are, for example, but not limited to, MgCl ₂ , zeolites, mineral clays, inorganic oxides such as talc, silica (SiO ₂ ), alumina (Al ₂ O ₃ ), silica-alumina, inorganic hydroxides, phosphates, sulfates and the like. It is a carrier known as a carrier material for a catalyst such as a finely divided solid porous support comprising a resinous resin or a resinous support such as a polyolefin comprising a polystyrene or a mixture thereof.

The carrier is modified with silane, aluminum alkyl, aluminoxane or the like or used as it is. The catalyst composition is also prepared by the original method.

Polymerization can be effected by known methods in the liquid phase as well as in the gas phase. In the case of a liquid reaction medium, both solution and suspension polymerization are suitable, whereas the amount of transition metals generally used is such that the concentration thereof in the dispersant is 10 ^-8 -10 ^-3 mol / l, preferably 10 ^-7 -10 ^-4 It is about mol / l.

Liquids that are inert to the catalyst system can be used as dispersants in the polymerization. One or more saturated straight or branched aliphatic hydrocarbons, such as butane, pentane, hexane, heptane, pentamethyl heptane or mineral oil fractions, for example light oil or essential oils, naphtha, kerosene or gas oils are suitable for this purpose. Do. Aromatic hydrocarbons such as benzene and toluene may be used, but it would be undesirable to use such solvents for production on a technical scale because of consideration of cost as well as safety. It is therefore desirable to use inexpensive aliphatic hydrocarbons or mixtures thereof as solvent in the petrochemical industry market on a technical scale in the polymerization process. If aliphatic hydrocarbons are used as the solvent, the solvent contains a small amount of aromatic hydrocarbons such as toluene. So, for example, if methyl aluminoxane (MAO) is used as the cocatalyst, toluene may be used as the solvent to feed the MAO in dissolved form to the polymerization reactor. Drying or purification is preferred if the solvent is used; This can be done without problems for those of ordinary skill in the art.

If the polymerization is carried out under pressure, the yield of polymer can be increased gradually and the catalyst residue content is lower. Chain regulators can be used to control the molecular weight and the amount of unsaturation of the copolymer obtained. It is preferable to provide hydrogen as a chain regulator.

The polymerization can also be carried out in several stages, continuously, as well as in parallel. If necessary, the catalyst composition, temperature, hydrogen concentration, pressure, residence time, etc. may vary from step to step. In this way, it is also possible to obtain products with broad molecular weight distributions.

The polymer solution obtained from the polymerization can be investigated by known methods. Usually the catalyst is deactivated at certain points during the processing of the polymer. Deactivation is also effected in known manner, for example by water or alcohol. Because of the use of the catalyst system in the process of the invention, the removal of catalyst residues can usually be omitted because the amount of catalyst in the polymer at the junction, in particular the content of halogens and transition metals, is very low.

Copolymers prepared according to the process of the present invention can be used for other applications, similar impact deformation, use in extrusion molding and wire-and-cable applications. The polymers are also useful for preparing rubber articles and modified rubber articles.

The invention will now be illustrated by the following non-limiting examples.

In the following, "Cp" means "cyclopentadienyl";"Me" means "methyl";"Bu" means "butyl";" ⁱ Pr" means "isopropyl".

Synthesis of Bidentate Monocyclopentadienyl Complex

Example I

Synthesis of (dimethylaminoethyl) tetramethylcyclopentadienyltitanium (III) dichloride (CpMe ₄ (CH ₂ ) ₂ NMe ₂ TiCl ₂ )

a) Preparation of 4-hydroxy-4- (dimethylamino-ethyl) -3,5-dimethyl-2,5-heptadiene

10.0 g of lithium (1.43 mol) in diethyl ether (300 mL) was added to 2-bromo-2-butene (108 g; 0.800 mol) with reflux for about 30 minutes. After stirring overnight (17 hours), ethyl-3- (N, N-dimethylamino) propionate (52.0 g; 0.359 mol) was added to the reaction mixture for about 15 minutes. After stirring for 30 minutes at room temperature, 200 ml of water was added dropwise. After separation, the aqueous phase was extracted twice with 50 ml of CH ₂ Cl ₂ . The organic phase was boiled and the residue was distilled off under reduced pressure. Yield was 51.0 g (67%).

b) Preparation of (dimethylaminoethyl) tetramethylcyclopentadiene

Carbinol (21.1 g; 0.10 mol) prepared as described in a) was added in part to p-toluenesulfonic acid. H ₂ O (28.5 g; 0.15 mol) dissolved in 200 ml of diethyl ether. After stirring for 30 minutes at room temperature, the reaction mixture was poured a solution of 50 g of Na ₂ CO ₃ · 10H ₂ O in 250 ml of water. After separation, the aqueous phase was extracted twice with 100 ml of diethyl ether. The combined ether layer was dried (Na ₂ SO ₄ ), filtered and boiled. The residue was then distilled off under reduced pressure. Yield was 11.6 g (60%).

c) Preparation of (dimethylaminoethyl) tetramethylcyclopentadienyltitanium (III) dichloride

1.0 equivalent (1.43 mL; 1.6 M) of n-BuLi was added to a solution of C ₅ Me ₄ H (CH ₂ ) ₂ NMe ₂ (0.442 g; 2.29 mmol) in b) in THF (50 mL) (after -60 ° C.). Cooling), and then the cooling bath was removed. After warming to room temperature, the solution was cooled to −100 ° C. and TiCl ₃ THF (0.8 g; 2.3 mmol) was added to a portion. After stirring for 2 hours at room temperature, THF was removed under reduced pressure. After adding a certain boiling gasoline, the complex (green solid) was purified by repeated solid washing, filtered and the solvent was distilled again. Sublimation can also yield pure complexes.

Example II

Synthesis of (dibutylaminoethyl) tetramethylcyclopentadienyltitanium (III) dichloride (CpMe ₄ (CH ₂ ) ₂ NBu ₂ TiCl ₂ )

a) Preparation of ethyl 3- (N, N-di-n-butylamino) propionate

Ethyl 3-bromopropionate (18.0 g; 0.10 mol) was carefully added to di-n-butylamine (25.8 g; 0.20 mol) and stirred for 2 hours. Then diethyl ether (200 mL) and pentane (200 mL) were added. The precipitate was filtered off, the filtrate was boiled and the residue was distilled off under reduced pressure. Yield was 7.0 g (31%).

b) Preparation of bis (2-butenyl) (di-n-butylaminoethyl) -methanol

As in Example I, 2-lithium-2-butene was prepared from 2-bromo-2-butene (16.5 g; 0.122 mol) and lithium (2.8 g; 0.4 mol). To this was added ester of a) (7.0 g; 0.031 mol) with reflux for about 5 minutes and stirred for about 30 minutes. Then water (200 mL) was carefully added dropwise. The aqueous layer was separated and extracted twice with 50 mL of CH ₂ Cl ₂ . The combined organic layer was washed once with 50 mL of water, dried (K ₂ CO ₃ ), filtered and boiled. Yield was 9.0 g (100%).

c) Preparation of (di-n-butylaminoethyl) tetramethylcyclopentadiene)

4.5 g (0.015 mol) of carbinol of b) was added dropwise to 40 ml of concentrated sulfuric acid at 0 ° C, and stirred at 0 ° C for 30 minutes. The reaction mixture was then poured into a mixture of 400 mL water and 200 mL hexane. The mixture was made alkaline with NaOH (60 g) while cooling in an ice bath. The aqueous layer was separated and extracted with hexane. The combined hexane layer was dried (K ₂ CO ₃ ), filtered and boiled. The residue was distilled off under reduced pressure. The boiling point was 110 ° C. (0.1 mm Hg) and the yield was 2.3 g (55%).

d) Preparation of (di-n-butylaminoethyl) tetramethylcyclopentadienyltitanium (III) dichloride

1.0 equivalent (0.75 mL; 1.6 M) of n-BuLi was added to a C ₅ Me ₄ H (CH ₂ ) ₂ NBu ₂ solution (0.332 g; 1.20 mmol) in c) in THF (50 mL) (afterwards at -60 ° C). Cooling), and then the cooling bath was removed. After warming to room temperature, the solution was cooled to −100 ° C. and TiCl ₃ THF (0.45 g; 1.20 mmol) was added in portions. After stirring for 2 hours at room temperature, THF was removed under reduced pressure. Purification was carried out as in Example I.

Example III

The catalyst is (dimethylaminomethyl) -diisopropyl-cyclopentadienyltitanium- (III) dichloride (CpH ₂ ⁱ Pr ₂ (CH ₂ ) ₂ NMe ₂ TiCl ₂ ).

a. Preparation of Di (2-propyl) cyclopentadiene

180 g clear 50% strength NaOH (2.25 mol), 9.5 g Aliquat 336 (23 mmol) and 15 g (0.227 mol) freshly broken cyclopentadiene in a 200 ml volume double wall reactor with baffle, condenser, tower stirrer, thermometer and dropping funnel Was combined. The reaction mixture was stirred vigorously at a speed of 1385 rpm for several minutes. Then 56 g (0.46 mol) of 2-propyl bromide were added while simultaneously cooling with water. After a few minutes 2-propyl bromide was added and the temperature rose to about 10 ° C. Then stirring was continued at 50 ° C. for 6 hours. GC was used to indicate that 92% of the di (2-propyl) cyclopentadiene is present in the mixture of di (2-propyl) cyclopentadiene and tri (2-propyl) cyclopentadiene. The product was distilled at 10 mbar and 70 ° C. After distillation, 25.35 g of di (2-propyl) cyclopentadiene was obtained. Characterization was performed by GC, GC-MS, ¹³ C-NMR and ¹ H-NMR.

b. Preparation of (dimethylaminoethyl) tri (2-propyl) cyclopentadiene

In a three-necked dry 500 ml flask with a magnetic stirrer, a 62.5 ml solution of n-butyllithium (1.6 M in n-hexane; 100 mmol) was added to triisopropyl-cyclo in 250 ml of THF at −60 ° C. under a dry nitrogen atmosphere. It was added to 19.2 g (100 mmol) pentadiene. After heating to room temperature (about 1 hour), stirring was continued for 2 hours. After cooling to -60 [deg.] C., an in-situ (dimethylaminoethyl) tosylate (105 mmol) solution was added over a 5 minute cycle. The reaction mixture was heated to room temperature and stirred overnight. After addition of water, the product was extracted with petroleum ether (40-60 ° C.). The combined organic layer was dried (Na ₂ SO ₄ ) and evaporated under reduced pressure. The conversion rate was 97%. Distillation gave dimethylamino-ethyldiisopropylcyclopentadiene and the yield was 54%.

c) [1- (dimethylaminoethyl) -2,4-di (2-propyl) cyclopentadienyltitanium (III) dichloride [C ₅ H ₂ (iPr) ₂ (CH ₂ ) ₂ NMe ₂ Ti (III) Synthesis of) Cl ₂ ]

To 25.2 ml of n-butyllithium (1.6 M, 40.3 mmol) in 8.9 g (40.3 mmol) of (dimethylaminoethyl) -di- (2-propyl) cyclopentadiene in 100 ml of tetrahydrofuran in a 250 ml flask Dropwise added. In a second three-neck flask, 100 ml of tetrahydrofuran was added to 14.93 g (40.3 mmol) of Ti (III) Cl ₃ THF. The two flasks were cooled to −60 ° C. and organolithium compounds were added to the Ti (III) Cl ₃ suspension. The reaction mixture containing 1- (dimethylaminoethyl) -2,4-di (2-propyl) cyclopentadienyltitanium (III) dichloride was slowly warmed to room temperature, and then stirring was continued for 18 hours.

Polymerization

The catalysts provided in Examples I, II and III were methylated with MeLi in diethyl ether.

Many continuous streams of petrol, propylene, ethylene catalyst and cocatalyst were placed in a 1-L reactor. This solution was continuously removed from the reactor. The catalyst is inactivated with isopropyl alcohol in a flash vessel; The solution was stabilized to about 1000 ppm Irganox 1076 ™. The polymer was analyzed after further processing.

Polymer analysis

The polymer composition was measured by Fourier Transform Infrared Spectroscopy (FT-IR). The FT-IR results show the composition of the various monomers in weight percent relative to the total composition.

Polymers prepared according to the examples were analyzed by SEC-DV. The molecular weight distribution was determined according to the universal calibration rule known from Z. Grubistic, R. Rempp, H. Benoit, J. Polym. Sci., Part B, 5,753 (1967).

Intrinsic viscosity (IV) was measured with decalin at 135 ° C.

The catalysts provided in Examples I, II and III were methylated with MeLi in diethyl ether.

Polymerization

Continuous streams of petrol, propylene, ethylene, catalyst and cocatalyst were placed in a 1-L reactor. This solution was continuously removed from the reactor. The catalyst is inactivated with isopropyl alcohol in a flash vessel; The solution was stabilized to about 1000 ppm Irganox 1076 ™. The polymer was analyzed after further processing.

Polymer analysis

The polymer composition was measured by Fourier Transform Infrared Spectroscopy (FT-IR). The FT-IR results show the composition of the various monomers in weight percent relative to the total composition.

Polymers prepared according to the examples were analyzed by SEC-DV. The molecular weight distribution is described by Z. Grubistic, R. Rempp, H. Benoit, J. Polym. Measurements were made in accordance with the Universal Correction Law described in Sci., Part B, 5,753 (1967), incorporated herein by reference.

Intrinsic viscosity (int. Visc. Or "IV") was determined by decalin at 135 ° C.

Example IV-III

Table 1 shows the polymerization conditions of the continuous polymerization of ethylene and propylene for Example IV-VII. This table describes the amounts of petroleum, propylene and ethylene, the amount of catalyst added, the amount of cocatalyst, the polymerization temperature and the polymerization time. Different catalysts are used for each example (prepared according to Examples I-III): Catalyst a is {Cp (Me) ₄ (CH ₂ ) ₂ NMe ₂ } TiMe ₂ , and catalyst b is {Cp (Me) ₄ ( CH ₂ ) ₂ NBu ₂ } TiMe ₂ , and catalyst c is {CpH ₂ ⁱ Pr ₂ (CH ₂ ) ₂ NMe ₂ } TiMe ₂ . The cocatalyst used in the examples is dimethylanilinium tetrakispentafluorophenylborate [HMe ₂ N- (C ₆ H ₅ )] ⁺ [(C ₆ H ₅ ) ₄ B] ^- .

The results of the continuous polymerization of Example IV-IX are summarized in Table 2. This table shows polymer production (yield (g / hour)), catalytic activity (kg of polymer / g of transition metal), composition of polymer (wt%) as measured by FT-IR, intrinsic viscosity of copolymer, SEC-DV The number average molecular weight (M _n ) and the absolute molecular weight distribution (MWD = M _w / M _n ) are shown.

Some examples of transition metal complexes useful in the process of the invention are shown in Table 3.

Experimental condition Example Petrol (kg / h) Propylene (g / h) Ethylene (g / h) Catalyst type Catalyst (mmol / h) Cocatalyst (mmol / h) Polymerization temperature (℃) Polymerization time (minutes) Ⅳ 2.22 652 319 a 0.026 0.1 158 10 Ⅴ 2.02 756 419 a 0.022 0.2 153 9 Ⅵ 2.34 412 445 a 0.020 0.08 123 10 Ⅶ 2.16 705 336 b 0.047 0.1 148 10 Ⅷ 2.04 839 317 c 0.2 0.4 148 10

Polymerization Result and Copolymer Analysis Result Example Yield (g / h) Activity (kg / g) % C3 (wt%) Ⅳ (dl / g) M _n (kg / mol) M _w (kg / mol) MWD Ⅳ 710 570 54 0.45 12 31 2.6 Ⅴ 630 600 50 0.98 27 63 2.3 Ⅵ 630 660 43 1.5 48 120 2.5 Ⅶ 640 280 54 0.79 nd nd nd Ⅷ 660 70 57 0.25 7 20 2.8

nd = not measured

Examples of transition metal complexes useful in the process of the invention (see Formula 1-5) M [e] L Y R D R ' K Ti Cl C ₅ H ₄ Dimethylsilyl N methyl L Zr F C ₅ Me ₄ Diethylsilyl P ethyl Y-R ' Hf Br Indenil Dipropylyl As profile X V I Fluorenyl Dibutylsilyl Sb n-butyl Diethyl ether Nb methyl Benzofluorenyl Methylamido O n-pentyl Tetrahydrofuran Ta Methoxy Octahydrofluorenyl Dimethylgermanyl S Methoxy Trimethylamine Cr Ethoxy C ₅ H ₃ (N-Bu) Diethylgermanyl Se Ethoxy Triethylamine Mo Hydride Tetrahydroindenyl Diethyl propylene Cl Trimethylphosphine W Isopropyloctylpropoxyphenoxybenzylmethylthio C ₅ H ₃ (SiMe ₃ ) methylamidophenylphosphido Tetramethyldisiloxanediphenylsilyltetramethylsilaethylenemethylenediethylmethyleneethylenedimethylethyleneethylphosphidophenylphosphido FBrIphenoxybenzyl H Triethylphosphinetriphenylphosphinedimethylsulfidedimethylaniline

Claims (20)

In the presence of a catalyst composed of a reduced transition metal complex and a cocatalyst, the polymerization of ethylene and at least one α-olefin is carried out under effective copolymerization conditions at temperatures of about 100 ° C. to about 220 ° C. To 90% by weight of an ethylene / α-olefin copolymer, The reduced transition metal complex compound has a structure of Formula 1, characterized in that the ethylene / α-olefin copolymer production method. (Formula 1) (In Formula 1, M is a reduced transition metal selected from group 4, 5 or 6 of the Periodic Table of the Elements; X is a multidentate monoanionic ligand represented by the general formula (Ar-R _t- ) _s Y (-R _t -DR ' _n ) _q ; Y is an element selected from the group consisting of cyclopentadienyl, amido (-NR'-) or phosphido (-PR'-) groups; R is at least one element selected from (i) a group consisting of a linking group between a Y group and a DR ' _n group and (ii) a linking group between a Y group and an Ar group, wherein the R groups are bonded to each other when the ligand X comprises one or more R groups Same or different; D is an electron-donor heteroatom selected from group 15 or 16 of the Periodic Table of the Elements; R ′ is a substituent selected from the group consisting of hydrogen, a hydrocarbon radical and a heteroatom-containing component, except that when it is directly bonded with an electron-donor heteroatom (D), it is a polydentate monoanionic ligand When (X) contains one or more substituents (R '), the substituents (R') are the same or different from one another; Ar is an electron-donor aryl group; L is a monoanionic ligand that is bound to the reduced transition metal (M), where the monoanionic ligand (L) is a ligand consisting of a cyclopentadienyl, amido (-NR'-) or phosphido (-PR'-) group Monoanionic ligands (L) may be the same as or different from each other; K is a neutral or anionic ligand that is bound to the reduced transition metal (M), wherein the transition metal complex contains one or more ligands (K), and the ligands (K) may be the same or different from each other; m is the number of K ligands, m is 0 for M ³⁺ , 1 for M ⁴⁺ , 2 for M ⁵⁺ when K ligand is an anionic ligand, and m is each for K One by one for the neutral K ligand; n is the number of R 'groups bonded to the electron-donor heteroatom (D), where n is 2 when D is selected from Group 15 of the Periodic Table of the Elements, n is 1 when D is selected from Group 16 of the Periodic Table of the Elements ; q and s are the number of (-R _t -DR ' _n ) groups and (Ar-R _t- ) groups respectively bonded to the Y group, and q + s is an integer of 1 or more; And t is (ⅰ) and Y and the number of R groups connecting each Ar group (ⅱ) the Y and DR _'n groups, wherein t is independently selected as 0 or 1) The method of claim 1, The Y group is a cyclopentadienyl group, characterized in that the production method. The method of claim 2, Wherein said cyclopentadienyl group is an unsubstituted or substituted indenyl, benzoindenyl or fluorenyl group. The method of claim 2, The reduced transition metal complex compound has a structure of formula (8): (In Formula 8, M (III) is a transition metal from Group 4 of the Periodic Table of the Elements in oxidation state 3+.) The method of claim 2, The reduced transition metal is a manufacturing method, characterized in that titanium. The method of claim 2, The electron-donor heteroatom (D) is a manufacturing method characterized in that the nitrogen. The method of claim 2, R 'in the DR' _n group is a process for producing n-alkyl groups. The method of claim 2, The R group is characterized in that it has a structure of formula (4): (Formula 4) (-CR ' _2- ) _p ' (In Formula 4, p is 1, 2, 3 or 4) The method of claim 2, The monoanion ligand (L) is characterized in that selected from the group consisting of halides, alkyl groups and benzyl groups. The method of claim 2, Y group is di-, tri- or tetraalkyl-cyclopentadienyl. The method of claim 2, The cocatalyst is characterized in that the linear or cyclic aluminoxane or triaryl borane or tetraaryl borate. The method of claim 2, At least one element selected from the group consisting of the reduced transition metal complex and the cocatalyst is supported on at least one carrier. The method of claim 1, Method for producing a copolymer having a number average molecular weight (M _n ) of 100 to 1,000,000. The method of claim 1, Method for producing a copolymer having a number average molecular weight (M _n ) of 100 to 30,000. The method of claim 3, wherein The copolymer is a manufacturing method, characterized in that prepared at a temperature of 135 ℃ to 220 ℃. The method of claim 1, Method for producing a copolymer having a number average molecular weight (M _n ) of 20,000 to 10,000. The method of claim 16, The copolymer is a manufacturing method, characterized in that prepared at a temperature of 115 ℃ to 180 ℃. The method of claim 1, Wherein said polymerization proceeds at a pressure of 100 MPa or less. The method of claim 1, The α-olefin is an element selected from the group consisting of propylene, 1-butene, 1-hexene, 1-octene and combinations thereof. The method of claim 21, The α-olefin is a propylene production method characterized in that.